Driving circuit of a touch display panel for reducing parasitic capacitances

ABSTRACT

A driving circuit configured to drive a touch display panel is provided. The driving circuit includes a signal generating circuit and a sensor driving circuit. The signal generating circuit is configurable to be coupled to gate lines of the touch display panel via a gate control circuit. The signal generating circuit modulates a plurality of voltage signals on a first driving signal and a second driving signal, and provides the modulated first driving signal and the modulated second driving signal to the gate control circuit to drive the gate lines during a sensing period. The sensor driving circuit is configurable to be coupled to sensor pads of the touch display panel. The sensor driving circuit modulates the voltage signals on a third driving signal, and drives the sensor pads with the modulated third driving signal during the sensing period. A method for driving a touch display panel is also provided.

CROSS-REFERENCE TO RELATED APPLICATION

This application is a continuation application of and claims thepriority benefit of a prior application Ser. No. 17/000,375, filed onAug. 24, 2020. The prior application Ser. No. 17/000,375, filed on Aug.24, 2020 is a continuation application of and claims the prioritybenefit of a prior application Ser. No. 15/086,073, filed on Mar. 31,2016. The prior application Ser. No. 15/086,073 claims the prioritybenefits of U.S. provisional application Ser. No. 62/207,366, filed onAug. 19, 2015. The entirety of the above-mentioned patent application ishereby incorporated by reference herein and made a part of thisspecification.

BACKGROUND OF THE INVENTION 1. Field of the Invention

The invention generally relates to an electronic circuit and a methodfor driving a panel, in particular, to a driving circuit and a methodfor driving a touch display panel.

2. Description of Related Art

In this information era, reliance on electronic products is increasingday by day. The electronic products including notebook computers, mobilephones, personal digital assistants (PDAs), digital walkmans, and so onare indispensable in our daily lives. Each of the aforesaid electronicproducts has an input interface for a user to input his or her command,such that an internal system of each of the electronic productspontaneously runs the command. At this current stage, the most commoninput interface includes a keyboard and a mouse.

From the user's aspect, it is sometimes rather inconvenient to use theconventional input interface including the keyboard and the mouse.Manufacturers aiming to resolve said issue thus start to equip theelectronic products with touch input interfaces, e.g. touch pads ortouch panels, so as to replace the conditional keyboards and mice. Atpresent, the users' commands are frequently given to the electronicproducts by physical contact or sensing relationship between users'fingers or styluses and the touch input interfaces. For instance, acapacitive touch input interface characterized by a multi-touch sensingfunction is more user-friendly than the conventional input interface andthus gradually becomes more and more popular.

However, when a touch panel is embedded into a display panel, parasiticcapacitances may be generated therebetween. The parasitic capacitanceswould have an impact on touch operation and reduce display quality.Hence, how to reduce the parasitic capacitances between the touch paneland the display panel to make a display touch apparatus havesatisfactory touch operation and good display quality without increasingthe manufacturing costs is one of the most important topics in thepertinent field.

SUMMARY OF THE INVENTION

Accordingly, the invention is directed to a driving circuit and a methodfor driving a touch display panel, capable of reducing parasiticcapacitances.

The invention provides a driving circuit configured to drive a touchdisplay panel. The driving circuit includes a signal generating circuitand a sensor driving circuit. The signal generating circuit isconfigurable to be coupled to gate lines of the touch display panel viaa gate control circuit. The signal generating circuit is configured tomodulate a plurality of voltage signals on a first driving signal and asecond driving signal, and provide the modulated first driving signaland the modulated second driving signal to the gate control circuit todrive the gate lines during a sensing period. The sensor driving circuitis configurable to be coupled to sensor pads of the touch display panel.The sensor driving circuit is configured to modulate the voltage signalson a third driving signal, and drive the sensor pads with the modulatedthird driving signal during the sensing period.

The invention provides a method for driving a touch display panel. Thetouch display panel includes a plurality of gate lines, a plurality ofdata lines, and a plurality of sensor pads. The method includes:modulating a plurality of voltage signals on a first driving signal, asecond driving signal, and a third driving signal during a sensingperiod; providing the modulated first driving signal and the modulatedsecond driving signal to a gate control circuit to drive the gate linesduring the sensing period; and driving the sensor pads with themodulated third driving signal during the sensing period.

The invention provides a display device. The display device includes atouch display panel, a gate control circuit, and a driving circuit. Thedriving circuit is configured to drive the touch display panel. Thedriving circuit includes a signal generating circuit and a sensordriving circuit. The signal generating circuit is coupled to gate linesof the touch display panel via the gate control circuit. The signalgenerating circuit is configured to modulate a plurality of voltagesignals on a first driving signal and a second driving signal, andprovide the modulated first driving signal and the modulated seconddriving signal to the gate control circuit to drive the gate linesduring a sensing period. The sensor driving circuit is coupled to sensorpads of the touch display panel. The sensor driving circuit isconfigured to modulate the voltage signals on a third driving signal,and drive the sensor pads with the modulated third driving signal duringthe sensing period.

According to the above descriptions, the plurality of voltage signalsare modulated on the first driving signal, the second driving signal andthe third driving signal in exemplary embodiments. The gate lines andthe sensor pads are driven by the modulated driving signals, and thedata lines are controlled to be electrically floating during the sensingperiod. Therefore, the parasitic capacitances are reduced.

To make the above features and advantages of the present disclosure morecomprehensible, several embodiments accompanied with drawings aredescribed in detail as follows.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings are included to provide a furtherunderstanding of the invention, and are incorporated in and constitute apart of this specification. The drawings illustrate embodiments of theinvention and, together with the description, serve to explain theprinciples of the invention.

FIG. 1 illustrates a schematic diagram of a touch panel and a sensordriving circuit according to an embodiment of the invention.

FIG. 2 illustrates a schematic waveform of a signal for driving sensorpads according to an embodiment of the invention.

FIG. 3 illustrates a schematic diagram of parasitic capacitances betweensensor electrodes and panel elements according to an embodiment of theinvention.

FIG. 4 illustrates an equivalent circuit diagram of the parasiticcapacitances depicted in FIG. 3 .

FIG. 5 illustrates schematic waveforms of signals for driving sensorpads and panel elements according to an embodiment of the invention.

FIG. 6 illustrates a schematic diagram of a display touch apparatushaving a low temperature poly-silicon (LTPS) touch panel according to anembodiment of the invention.

FIG. 7 illustrates a schematic diagram of a display touch apparatushaving an amorphous silicon (a-Si) touch panel according to anembodiment of the invention.

FIG. 8 illustrates a schematic diagram of a display touch apparatusaccording to an embodiment of the invention.

FIG. 9 illustrates a block diagram of a determination circuit accordingto an embodiment of the invention.

FIG. 10 is a flowchart illustrating steps in a method for driving adisplay panel having a touch panel according to an embodiment of theinvention.

DESCRIPTION OF THE EMBODIMENTS

Reference will now be made in detail to the present preferredembodiments of the invention, examples of which are illustrated in theaccompanying drawings. Wherever possible, the same reference numbers areused in the drawings and the description to refer to the same or likeparts.

The term “coupling/coupled” used in this specification (includingclaims) of the disclosure may refer to any direct or indirect connectionmeans. For example, “a first device is coupled to a second device”should be interpreted as “the first device is directly connected to thesecond device” or “the first device is indirectly connected to thesecond device through other devices or connection means.” In addition,the term “signal” can refer to a current, a voltage, a charge, atemperature, data, electromagnetic wave or any one or multiple signals.

FIG. 1 illustrates a schematic diagram of a touch panel and a sensordriving circuit according to an embodiment of the invention. FIG. 2illustrates a schematic waveform of a signal for driving sensor padsaccording to an embodiment of the invention. Referring to FIG. 1 andFIG. 2 , a touch panel 300 of the present embodiment includes aplurality of sensor pads 310. The sensor pads 310 are arranged in anarray. A sensor driving circuit 120 is coupled to the sensor pads 310.The sensor driving circuit 120 drives the sensor pads 310 with amodulated driving signal as illustrated in FIG. 2 during a sensingperiod in the present embodiment.

To be specific, a whole common electrode of a display panel is dividedinto the plurality of sensor pads 310 in the present embodiment. In adisplay period, the sensor pads 310 serve as common electrodes. In thesensing period, the sensor pads 310 serve as sensor electrodes. Thesensor driving circuit 120 modulates voltage signals VML, VMM and VMH ona driving signal VCOM to generate the modulated driving signal asillustrated in FIG. 2 . In the present embodiment, the driving signalVCOM may be a signal applied to the common electrodes in the displayperiod. When the sensor pads 310 serve as the sensor electrodes in thesensing period, the sensor driving circuit 120 drives the sensor pads310 with the modulated driving signal 230 via sensor trace 312. Next, ananalog-front-end (AFE) circuit calculates capacitive variations of eachof the sensor pads 310 relative to ground, so as to determine whether atouch event happens.

In the present embodiment, the touch panel 300 may be embedded into thedisplay panel in a manner of in-cell or on-cell, and the invention isnot limited thereto. Enough teaching, suggestion, and implementationillustration for the aforesaid touch panel may be obtained withreference to common knowledge in the related art, which is not repeatedhereinafter.

FIG. 3 illustrates a schematic diagram of parasitic capacitances betweensensor electrodes and panel elements according to an embodiment of theinvention. Referring to FIG. 3 , sensor pads SP-A, SP-B, SP-C and SP-Dare disposed above a plurality of data lines DL[n] to DL[n+3], aplurality of gate lines GL[n] to GL[n+2], and a plurality of pixelelectrodes 520, where n is an integer large than or equal to 1. Each ofthe sensor pads SP-A, SP-B, SP-C and SP-D includes a plurality ofsub-common electrodes 521 in the present embodiment. The plurality ofsub-common electrodes 521 are electrically connected to form a singlesensor pad, e.g. the sensor pad SP-A, SP-B, SP-C or SP-D. In addition,sensor trances ST[n] and ST[n+1] connects the sensor pads SP-A, SP-B,SP-C and SP-D and a sensor driving circuit. In the present embodiment,parasitic capacitances Csd, Cdg, Csg and Csp may be generated among thesensor electrodes and the panel elements. For example, the parasiticcapacitance Csd may be generated between the sensor electrode and thedata line, the parasitic capacitance Cdg may be generated between thedata line and the gate line, the parasitic capacitance Csg may begenerated between the sensor electrode and the gate line, and theparasitic capacitance Csp may be generated between the sensor electrodeand the pixel electrode.

FIG. 4 illustrates an equivalent circuit diagram of the parasiticcapacitances depicted in FIG. 3 . FIG. 5 illustrates schematic waveformsof signals for driving sensor pads and panel elements according to anembodiment of the invention. Referring to FIG. 1 , FIG. 4 and FIG. 5 ,the parasitic capacitances Csd and Cdg are coupled in series in thepresent embodiment. When the sensor driving circuit 120 drives thesensor pads 310 with the modulated third driving signal 230 via thesensor trace 312, the data lines, e.g. DL[n] to DL[n+3], are controlledto be electrically floating during the sensing period. In the presentembodiment, the pixel electrodes 520 may also be controlled to beelectrically floating during the sensing period. At the same time, afirst driving signal VGH and a second driving signal VGL are modulatedwith the voltage signals VML, VMM and VMH to generate the modulatedfirst driving signal 210 and the modulated second driving signal 220,respectively. The gate lines, e.g. GL[n] to GL[n+2], are driven by themodulated first driving signal 210 and the modulated second drivingsignal 220 during the sensing period. In the present embodiment, thefirst driving signal VGH and the second driving signal VGL may besignals that are respectively applied to a VGH power line and a VGLpower line in the display period.

In the present embodiment, the waveforms of the modulated first drivingsignal 210, the modulated second driving signal 220, and the modulatedthird driving signal 230 are substantially identical as shown in FIG. 5. For example, during the sensing period, each of the modulated firstdriving signal 210, the modulated second driving signal 220, and themodulated third driving signal 230 may have a plurality of stepwaveforms located in corresponding timing. In the present embodiment,since the data lines are electrically floating, and the waveforms of thefirst driving signal VGH and the second driving signal VGL are modulatedto be similar to that of the third driving signal VCOM during thesensing period, the parasitic capacitances Csd and Cdg are effectivelyreduced. In the present embodiment, voltage levels of the first drivingsignal VGH, the second driving signal VGL and the third driving signalVCOM may be the same or different according to design requirements, andthe invention is not limited thereto.

FIG. 6 illustrates a schematic diagram of a display touch apparatushaving a low temperature poly-silicon (LIPS) touch panel according to anembodiment of the invention. Referring to FIG. 6 , data lines DL arecontrolled by multiplexer circuits 634 on a LIPS touch panel 640, andgate lines GL are controlled by a gate control circuit 614 in thepresent embodiment. Operation voltages and control/driving signals ofthe multiplexer circuits 634 and the gate control circuit 614 areprovided by an external gate driver 612. The gate driver 612 is arrangedout of the LIPS touch panel 640. The gate driver 612 controls themultiplexer circuits 634 located on the LIPS touch panel 640 to turn offthe output of the multiplexer circuits 634 during the sensing period,and thus the data lines DL are floating in the present embodiment. Inone embodiment, the outputs SOUT[1] to SOUT[N] of the source driver 632may be coupled to the data lines DL via a switch circuit, and the switchcircuit is controlled to make the data lines DL electrically floating bya control signal during the sensing period, where N is an integer largethan or equal to 4. In the present embodiment, the gate driver 612 alsocontrols the output of the gate control circuit 614 located on the LIPStouch panel 640 to turn off the gate terminals of the thin filmtransistors, e.g. 300 depicted in FIG. 3 , during the sensing period,and thus the pixel electrodes, e.g. 520 depicted in FIG. 3 , arefloating in the present embodiment. In the present embodiment, thewaveforms of the first driving signal VGH and the second driving signalVGL are modulated to be similar to that of the third driving signal VCOMduring the sensing period as illustrated in FIG. 5 , and thus theparasitic capacitances Csd and Cdg are effectively reduced.

FIG. 7 illustrates a schematic diagram of a display touch apparatushaving an amorphous silicon (a-Si) touch panel according to anembodiment of the invention. Referring to FIG. 7 , data lines DL andgate lines GL are respectively controlled by an external source driver730 and an external gate driver 710 in the present embodiment. Thesource driver 730 and the gate driver 710 are arranged out of the a-Sitouch panel 740. In the present embodiment, the source driver 730 iscoupled to the data lines DL of the a-Si touch panel 740 via a switchcircuit 750. The switch circuit 750 is controlled to electrically floatthe data lines DL by a control signal S2 during the sensing period. Inthe present embodiment, the control signal S2 may be provided by thesource driver 730, the gate driver 710, a timing control circuit, orother similar circuits according to design requirements, and it is notlimited in the invention. In the present embodiment, the gate driver 710also turns off the gate terminals of the thin film transistors, e.g. 300depicted in FIG. 3 , via the gate lines GL during the sensing period,and thus the pixel electrodes, e.g. 520 depicted in FIG. 3 , arefloating in the present embodiment. In the present embodiment, thewaveforms of the first driving signal VGH and the second driving signalVGL are modulated to be similar to that of the third driving signal VCOMduring the sensing period as illustrated in FIG. 5 , and thus theparasitic capacitances Csd and Cdg are effectively reduced.

FIG. 8 illustrates a schematic diagram of a display touch apparatusaccording to an embodiment of the invention. Referring to FIG. 8 , thedisplay touch apparatus 800 of the present embodiment includes a drivingcircuit 830 and a display panel 850. The display panel 850 includes atouch panel 840. The driving circuit 830 is configured to drive thedisplay panel 850. The driving circuit 830 includes a signal generatingcircuit 810 and a sensor driving circuit 820. In the present embodiment,the signal generating circuit 810 modulates a plurality of voltagesignals VML, VMM and VMH on a first driving signal VGH and a seconddriving signal VGL, and drives the gate lines, e.g. GL depicted in FIG.6 or FIG. 7 , with the modulated first driving signal 210 and themodulated second driving signal 220 during a sensing period. In thepresent embodiment, the sensor driving circuit 820 modulates the voltagesignals VML, VMM and VMH on a third driving signal VCOM, and drives thesensor pads, e.g. SP depicted in FIG. 6 or FIG. 7 , with the modulatedthird driving signal 230 during the sensing period. In the presentembodiment, the data lines, e.g. DL depicted in FIG. 6 or FIG. 7 , arecontrolled to be electrically floating during the sensing period, andwaveforms of the modulated first driving signal 210, the modulatedsecond driving signal 220, and the modulated third driving signal 230are substantially identical. In addition, the voltage signals VML, VMMand VMH and the driving signals VGH, VGL, VCOM and GND may be providedby a power generator circuit (not shown) in the present embodiment.

To be specific, the signal generating circuit 810 includes a gate drivercircuit 812, a first signal modulation circuit 814, and a controlcircuit 816 in the present embodiment. The gate driver circuit 812 iscoupled to the gate lines. The gate driver circuit 812 operates betweenthe modulated first driving signal 210 and the modulated second drivingsignal 220 during the sensing period, and outputs the modulated firstdriving signal 210 and the modulated second driving signal 220 to thecoupled gate lines. The first signal modulation circuit 814 is coupledto the gate driver circuit 812. The first signal modulation circuit 814receives the voltage signals VML, VMM and VMH, and modulates the voltagesignals VML, VMM and VMH on the first driving signal VGH and the seconddriving signal VGL.

In the present embodiment, the first signal modulation circuit 814includes a first modulation channel 815 and a second modulation channel817. The first modulation channel 815 receives the voltage signals VML,VMM and VMH, and modulates the voltage signals VML, VMM and VMH on thefirst driving signal VGH. The second modulation channel 817 receives thevoltage signals VML, VMM and VMH, and modulates the voltage signals VML,VMM and VMH on the second driving signal VGL. In the present embodiment,each of the first modulation channel 815 and the second modulationchannel 817 includes a capacitor and a multiplexer circuit. Taking thefirst modulation channel 815 for example, the capacitor C1 is coupled tothe gate driver circuit 812. The capacitor C1 modulates the voltagesignals VML, VMM and VMH on the first driving signal VGH. Themultiplexer circuit MUX1 is coupled to the gate driver circuit 812 viathe capacitor C1. The multiplexer circuit MUX1 is controlled tosequentially transmit the voltage signals VML, VMM and VMH to thecapacitor C1 by one of a plurality of control signals S1. Elements andoperations of the second modulation channel 817 may be deduced byanalogy according to descriptions of the first modulation channel 815,and it is not further described herein. In the present embodiment, thecontrol circuit 816 outputs the plurality of control signals S1 tocontrol the multiplexer circuits MUX1 and MUX2. The multiplexer circuitsMUX1 and MUX2 select one of the voltage signals VML, VMM, VMH and GNDaccording to the control signals S1, and thus output the selected signalto the capacitors C1 and C2, respectively.

In the present embodiment, the sensor driving circuit 820 includes asecond signal modulation circuit 822, and the second signal modulationcircuit 822 includes a plurality of third modulation channels 823. Inthe present embodiment, each of the third modulation channels 823includes a multiplexer circuit MUX3. The multiplexer circuits MUX3receive the voltage signals VML, VMM and VMH, and modulate the voltagesignals VML, VMM and VMH on the third driving signal VCOM according tothe plurality of control signals S1.

In the present embodiment, the sensor pads are grouped into activesensor pads and non-active sensor pads during the sensing period. Themultiplexer circuits MUX3 coupled to the non-active sensor pads, i.e.the multiplexer circuits MUX3 located in the non-active sensing region,are controlled to sequentially transmit the voltage signals VML, VMM,VMH, GND and VCOM to the touch panel 840 by the plurality of controlsignals S1. The multiplexer circuits MUX3 coupled to the active sensorpads, i.e. the multiplexer circuits MUX3 located in the active sensingregion, are controlled to transmit sensing signals S3 to a determinationcircuit 900 by the plurality of control signals S1. In the presentembodiment, the determination circuit 900 may include a plurality ofanalog-front-end (AFE) circuits respectively denoted by AFE[a], AFE[b],AFE[c] and AFE[d], as illustrated in FIG. 9 . FIG. 9 illustrates a blockdiagram of a determination circuit according to an embodiment of theinvention. Enough teaching, suggestion, and implementation illustrationfor the aforesaid determination circuit and AFE circuits may be obtainedwith reference to common knowledge in the related art, which is notrepeated hereinafter.

In the present embodiment, the waveforms of the first driving signal VGHand the second driving signal VGL are modulated to be similar to that ofthe third driving signal VCOM during the sensing period as illustratedin FIG. 5 , and the data lines, e.g. DL depicted in FIG. 6 or FIG. 7 ,are controlled to be electrically floating during the sensing period.Therefore, the parasitic capacitances Csd and Cdg are effectivelyreduced.

FIG. 10 is a flowchart illustrating steps in a method for driving adisplay panel having a touch panel according to an embodiment of theinvention. Referring to FIG. 6 to FIG. 8 and FIG. 10 , the method fordriving the display panel having the touch panel of the presentembodiment is at least adapted to one of the display touch apparatus 600of FIG. 6 , the display touch apparatus 700 of FIG. 7 , and the displaytouch apparatus 800 of FIG. 8 , but the invention is not limitedthereto. Taking the display touch apparatus 800 of FIG. 8 for example,in step S100, the driving circuit 830 modulates a plurality of voltagesignals VML, VMM and VMH on a first driving signal VGH, a second drivingsignal VGL, and a third driving signal VCOM during a sensing period. Instep S110, the driving circuit 830 drives the gate lines GL with themodulated first driving signal 210 and the modulated second drivingsignal 220 during the sensing period, and drives the sensor pads SP withthe modulated third driving signal 230 during the sensing period. Instep S120, the driving circuit 830 controls the data lines DL to beelectrically floating during the sensing period.

Besides, the method for driving the display panel having the touch paneldescribed in the present embodiment of the invention is sufficientlytaught, suggested, and embodied in the embodiments illustrated in FIG. 1to FIG. 9 , and therefore no further description is provided herein.

In summary, in the exemplary embodiment of the invention, the firstdriving signal and the second driving signal are modulated to drive thegate lines of the display panel during the sensing period, and the thirddriving signal is also modulated to drive the sensor pads of the touchpanel. The waveforms of the modulated first driving signal, themodulated second driving signal, and the modulated third driving signalare substantially identical. The data lines of the display panel arecontrolled to be electrically floating during the sensing period.Therefore, the parasitic capacitances between the sensor pads and thedata lines and the parasitic capacitances between the data lines and thegate lines are effectively reduced.

It will be apparent to those skilled in the art that variousmodifications and variations can be made to the structure of the presentinvention without departing from the scope or spirit of the invention.In view of the foregoing, it is intended that the present inventioncover modifications and variations of this invention provided they fallwithin the scope of the following claims and their equivalents.

What is claimed is:
 1. A driving circuit configured to drive a touchdisplay panel comprising sensor pads, and the driving circuitcomprising: a signal generating circuit, configurable to be coupled togate lines of the touch display panel via a gate control circuit, andconfigured to modulate a plurality of voltage signals on a first drivingsignal and a second driving signal, and provide the modulated firstdriving signal and the modulated second driving signal to the gatecontrol circuit to drive the gate lines during a sensing period; and asensor driving circuit, configurable to be coupled to the sensor pads ofthe touch display panel, and configured to modulate the voltage signalson a third driving signal, and drive the sensor pads with the modulatedthird driving signal during the sensing period, wherein the sensor padsare grouped into active sensor pads and non-active sensor pads, and thesensor driving circuit comprises: a signal modulation circuit,configurable to be coupled to the sensor pads, wherein the signalmodulation circuit comprises: a plurality of third modulation channels,configurable to be coupled to the active and non-active sensor pads,receiving the voltage signals, and modulating the voltage signals on thethird driving signal, wherein the third modulation channels coupled tothe non-active sensor pads sequentially transmit the voltage signals tothe touch display panel, and wherein the third modulation channelscoupled to the active sensor pads transmit sensing signals to adetermination circuit.
 2. The driving circuit according to claim 1,wherein the modulated first driving signal and the modulated seconddriving signal have a substantially identical waveform and differentvoltage levels during the sensing period.
 3. The driving circuitaccording to claim 1, wherein waveforms of the modulated first drivingsignal, the modulated second driving signal, and the modulated thirddriving signal are substantially identical.
 4. The driving circuitaccording to claim 1, wherein the signal generating circuit comprises: agate driver circuit, configurable to be coupled to the gate controlcircuit, and configured to output the modulated first driving signal andthe modulated second driving signal to the gate control circuit; and afirst signal modulation circuit, coupled to the gate driver circuit, andconfigured to receive the voltage signals, and modulate the voltagesignals on the first driving signal and the second driving signal. 5.The driving circuit according to claim 4, wherein the first signalmodulation circuit comprises: a first modulation channel, coupled to thegate driver circuit, and configured to receive the voltage signals, andmodulate the voltage signals on the first driving signal; and a secondmodulation channel, coupled to the gate driver circuit, and configuredto receive the voltage signals, and modulate the voltage signals on thesecond driving signal.
 6. The driving circuit according to claim 1,further comprising: a source driving circuit, configurable to be coupledto data lines of the touch display panel, wherein the data lines arecontrolled to be electrically floating during the sensing period.
 7. Thedriving circuit according to claim 6, wherein the source driving circuitis configurable to be coupled to the data lines of the touch displaypanel via a switch circuit, and the switch circuit is controlled toelectrically float the data lines by a control signal during the sensingperiod.
 8. The driving circuit according to claim 6, wherein the sourcedriving circuit is configurable to be coupled to the data lines of thetouch display panel via a plurality of multiplexer circuits, and outputsof the multiplexer circuits are controlled to be turned off toelectrically float the data lines by the signal generating circuitduring the sensing period.
 9. A method for driving a touch displaypanel, wherein the touch display panel comprises a plurality of gatelines, a plurality of data lines, and a plurality of sensor pads, andthe method comprising: modulating a plurality of voltage signals on afirst driving signal, a second driving signal, and a third drivingsignal during a sensing period; providing the modulated first drivingsignal and the modulated second driving signal to a gate control circuitto drive the gate lines during the sensing period; and driving thesensor pads with the modulated third driving signal during the sensingperiod, wherein the sensor pads are grouped into active sensor pads andnon-active sensor pads, and the method further comprises: sequentiallytransmitting the voltage signals to the touch display panel viamodulation channels coupled to the non-active sensor pads; andtransmitting sensing signals to a determination circuit via modulationchannels coupled to the active sensor pads.
 10. The method according toclaim 9, wherein the modulated first driving signal and the modulatedsecond driving signal have a substantially identical waveform anddifferent voltage levels during the sensing period.
 11. The methodaccording to claim 9, wherein waveforms of the modulated first drivingsignal, the modulated second driving signal, and the modulated thirddriving signal are substantially identical.
 12. The method according toclaim 9, further comprising: controlling the data lines to beelectrically floating during the sensing period.
 13. The methodaccording to claim 12, wherein the data lines are coupled to a switchcircuit, and the step of controlling the data lines to be electricallyfloating during the sensing period comprises: controlling the switchcircuit to electrically float the data lines according to a controlsignal during the sensing period.
 14. The method according to claim 12,wherein the data lines are coupled to a plurality of multiplexercircuits, and the step of controlling the data lines to be electricallyfloating during the sensing period comprises: controlling outputs of themultiplexer circuits to be turned off to electrically float the datalines during the sensing period.
 15. A display device, comprising: atouch display panel, comprising a plurality of gate lines, a pluralityof data lines, and a plurality of sensor pads, wherein the sensor padsare grouped into active sensor pads and non-active sensor pads; a gatecontrol circuit, coupled to the gate lines of the touch display panel;and a driving circuit, configured to drive the touch display panel andcomprising: a signal generating circuit, coupled to the gate lines ofthe touch display panel via the gate control circuit, and configured tomodulate a plurality of voltage signals on a first driving signal and asecond driving signal, and provide the modulated first driving signaland the modulated second driving signal to the gate control circuit todrive the gate lines during a sensing period; and a sensor drivingcircuit, coupled to the sensor pads of the touch display panel, andconfigured to modulate the voltage signals on a third driving signal,and drive the sensor pads with the modulated third driving signal duringthe sensing period, wherein the signal modulation circuit comprises: aplurality of third modulation channels, configurable to be coupled tothe active and non-active sensor pads, receiving the voltage signals,and modulating the voltage signals on the third driving signal, whereinthe third modulation channels coupled to the non-active sensor padssequentially transmit the voltage signals to the touch display panel,and wherein the third modulation channels coupled to the active sensorpads transmit sensing signals to a determination circuit.
 16. Thedisplay device according to claim 15, wherein the modulated firstdriving signal and the modulated second driving signal have asubstantially identical waveform and different voltage levels during thesensing period.
 17. The display device according to claim 15, whereinwaveforms of the modulated first driving signal, the modulated seconddriving signal, and the modulated third driving signal are substantiallyidentical.
 18. The display device according to claim 15, wherein thesignal generating circuit comprises: a gate driver circuit, coupled tothe gate control circuit, and configured to output the modulated firstdriving signal and the modulated second driving signal to the gatecontrol circuit; and a first signal modulation circuit, coupled to thegate driver circuit, and configured to receive the voltage signals, andmodulate the voltage signals on the first driving signal and the seconddriving signal.
 19. The display device according to claim 18, whereinthe first signal modulation circuit comprises: a first modulationchannel, coupled to the gate driver circuit, and configured to receivethe voltage signals, and modulate the voltage signals on the firstdriving signal; and a second modulation channel, coupled to the gatedriver circuit, and configured to receive the voltage signals, andmodulate the voltage signals on the second driving signal.
 20. Thedisplay device according to claim 15, wherein the driving circuitfurther comprises: a source driving circuit, coupled to the data linesof the touch display panel, wherein the data lines are controlled to beelectrically floating during the sensing period.
 21. The display deviceaccording to claim 20, wherein the source driving circuit is coupled tothe data lines of the touch display panel via a switch circuit, and theswitch circuit is controlled to electrically float the data lines by acontrol signal during the sensing period.
 22. The display deviceaccording to claim 20, wherein the source driving circuit is coupled tothe data lines of the touch display panel via a plurality of multiplexercircuits, and outputs of the multiplexer circuits are controlled to beturned off to electrically float the data lines by the signal generatingcircuit during the sensing period.
 23. The display device according toclaim 22, wherein the multiplexer circuits are disposed on the touchdisplay panel.
 24. The display device according to claim 15, wherein thegate control circuit is disposed on the touch display panel.